Global Sources
EE Times-India
Stay in touch with EE Times India
EE Times-India > Manufacturing/Packaging

Materials interface research opens path to better solar cells

Posted: 21 Apr 2014     Print Version  Bookmark and Share

Keywords:Center for Free-Electron Laser Science  solar cell  interface  superconductor  hard-disk drive 

A team of scientists has used Deutsches Elektronen-Synchrotron's bright research light sources to advance their understanding of the interface of two materials that may improve the performance of solar cells, novel superconductors and smaller hard-disk drives. The research reported in the scientific journal Nature Communications enhances the understanding of the interface of two materials, where completely new properties can arise, the researchers noted.

With their work, the team of Andrivo Rusydi from the National University of Singapore and Michael Rbhausen from the Hamburg Center for Free-Electron Laser Science (CFEL) have solved a long standing mystery in the physics of condensed matter. CFEL is a cooperation of DESY, the University of Hamburg and the Max Planck Society.

Lanthanum aluminate layer

Left: If the lanthanum aluminate layer (blue) is less than three unit cells, the electrons redistribute in sub-layers. Right: If the layer has four unit cells or more, some electrons migrate to the interface. (Credit: Michael Rbhausen, University of Hamburg)

"Interfaces are a hot topic in materials research," explained Rusydi. "If two dissimilar materials are put together, completely new properties may be generated. For instance, two insulators and non-magnetic materials can become metallic and magnetic at their interface." The reason for this change of personality of the two materials is the broken symmetry at the interface, explained Rbhausen, who is a professor at the University of Hamburg. "The two materials have different characteristics and different structures. If you put them together, they have to make a deal and rearrange, and this leads to new properties."

Making use of these phenomena can lead to smaller hard-drives, for example. "Conventional hard-drives are currently controlled by bulk physical properties of the material, for miniaturisation we would like to control their physical properties by the interface structure," said Rusydi. "The problem is that we do not yet fully understand what is happening at the interface."

As an example, the team investigated the interface of strontium titanate (SrTiO3) and lanthanum aluminate (LaAlO3), two insulators that become conductors at their interface. "However, based on Maxwells theory, a tenfold higher conductivity should be observed. So, 90 per cent of the charge carriers, the electrons, have gone missing. That was a complete mystery to us," said Rusydi.

1 • 2 Next Page Last Page

Comment on "Materials interface research opens p..."
*  You can enter [0] more charecters.
*Verify code:


Visit Asia Webinars to learn about the latest in technology and get practical design tips.


Go to top             Connect on Facebook      Follow us on Twitter      Follow us on Orkut

Back to Top